The molecule contains four carbon atoms arranged in a ring with a triple bond between two of them.这个分子包含四个呈环状排列的碳原子，每两个碳原子之间形成一个三价键。The stone circle at Avebury is larger than Stonehenge.埃夫伯里的史前环状巨石阵比索尔兹伯里的巨石阵规模还要大。The road goes round in a loop and rejoins the main road about 2 kilometres past the town.这条路呈环状，在离镇子两公里处又与主干道连结上。